Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/core/inspector/ConsoleMessage.cpp

 /*
  * Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Matt Lilek <webkit@mattlilek.com>
  * Copyright (C) 2009, 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
@@ skipping 62 matching lines @@
     , m_timestamp(WTF::currentTime())
 {
     autogenerateMetadata(canGenerateCallStack, state);
 }
 
 ConsoleMessage::ConsoleMessage(bool, MessageSource source, MessageType type, MessageLevel level, const String& message, PassRefPtr<ScriptCallStack> callStack, unsigned long requestIdentifier)
     : m_source(source)
     , m_type(type)
     , m_level(level)
     , m_message(message)
-    , m_arguments(0)
+    , m_arguments(nullptr)
     , m_line(0)
     , m_column(0)
     , m_repeatCount(1)
     , m_requestId(IdentifiersFactory::requestId(requestIdentifier))
     , m_timestamp(WTF::currentTime())
 {
     if (callStack && callStack->size()) {
         const ScriptCallFrame& frame = callStack->at(0);
         m_url = frame.sourceURL();
         m_line = frame.lineNumber();
@@ skipping 191 matching lines @@
 
 unsigned ConsoleMessage::argumentCount()
 {
     if (m_arguments)
         return m_arguments->argumentCount();
     return 0;
 }
 
 } // namespace WebCore